346 Mr. W. Arnold Lewis on 
fied; our own Haworth “named simultaneously” the 
two sexes of Miana arcuosa, the name arcuosa beng 
given to the male. No one terms the species anything 
else than arcwosa, and Dr. Knaggs does not suggest that, 
according to his canon, the name minima (given to the 
female) must be accepted instead. 
The reason he does not is, perhaps, the same which 
would control the action of any adventurous writer. A 
principle can be stated, and supported as a principle, 
without encountering any vigorous opposition. Hntomo- 
logists at large do not know enough to see its effect, and 
choose not to quarrel with a learned writer till he makes 
an overt attack. Dr. Knaggs avoids encountering the 
displeasure of the collectors, but he does so at the cost 
of acknowledging that Communis error facit jus. 
But do not the English entomologists demand better 
work than this? Theory and practice are not on speak- 
ing terms in Dr. Knaggs’ list. Let us hope a list of 
labels will never again assume to introduce changes, or 
lay down a law. 
Mr. Newman’s “‘ Natural History of British Moths” is 
a work extensively used by collectors of the unscientific 
class. The sort of practical joke, by which the later 
English writers carry off—I speak without offence—their 
autocratic manner, is played more than once in this book. 
The joke is almost de rigueur with authors on Lepidop- 
terology. It consists in an assumption on the part of the 
writer, that he is addressing children, and a continual 
reference to his readers’ youthfulness and inexperience. 
No one writes on the Lepidoptera for grown people! It 
is a very remarkable thing that the books now are always 
published for “the young collector.” This is very 
pleasant for the authors, because they are saved a great 
deal of trouble. You do not give the reasons for things 
to children; they are satisfied without; and in a book 
written ostensibly for children, no one looks for anything 
very thorough or deep. It would be a pity, however, 
that an author should carry even this joke too far, be- 
cause it might unjustly be imputed that he bid for the 
approval of the unscientific. [ am beginning to fear 
that we shall not have any more English books that are 
not addressed to the school-room; and I have no expec- 
tation but that the title-page of the forthcoming work 
